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Hi, I'm replacing the disc brakes on my Alfa 75 3.0 V6, and some of the bolts in the rear brake discs are rounded. I've managed to get them out after hours of work, however now i need some new bolts.

Can anyone assist in sourcing some of these bolts? There are 6 in each disc - M10 43.5mm long with a thread pitch of 1mm. Part number 60533889.

I've rang just about every Alfa parts specialist on Google.

Cheers!
 

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Firstly, although I don't know for certain, I am quite sure they are M10x1.25mm thread pitch. M10x1mm is usually reserved for brake pipe unions. It is a very fine thread. Standard metric coarse is M10x1.5mm.
In other words, the thread pitch should be the same as metric coarse M8.

eBay, from Hong Kong;
https://m.ebay.co.uk/itm/M10x45mm-1mm-Pitch-304-Stainless-Steel-Hex-Socket-Head-Cap-Screws-Bolts-2pcs/302606895228?_trkparms=aid=555017&algo=PL.CASSINI&ao=1&asc=20151028122843&meid=9073d0ed0e9f4a56a73f5cc9000380e6&pid=100386&rk=1&rkt=1&&itm=302606895228&_trksid=p2047936.c100386.m102&_mwBanner=1&_rdt=1

Or try Amazon. M40 may be too short but you could cut down a slightly longer bolt easily enough. It is best to fit a nut before cutting and then chamfer the end slightly to make fitting easier.
https://www.amazon.co.uk/s?k=m10+1.25+cap+screw&ref=nb_sb_noss
 

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Firstly, although I don't know for certain, I am quite sure they are M10x1.25mm thread pitch. M10x1mm is usually reserved for brake pipe unions. It is a very fine thread. Standard metric coarse is M10x1.5mm.
In other words, the thread pitch should be the same as metric coarse M8.

eBay, from Hong Kong;
https://m.ebay.co.uk/itm/M10x45mm-1mm-Pitch-304-Stainless-Steel-Hex-Socket-Head-Cap-Screws-Bolts-2pcs/302606895228?_trkparms=aid=555017&algo=PL.CASSINI&ao=1&asc=20151028122843&meid=9073d0ed0e9f4a56a73f5cc9000380e6&pid=100386&rk=1&rkt=1&&itm=302606895228&_trksid=p2047936.c100386.m102&_mwBanner=1&_rdt=1

Or try Amazon. M40 may be too short but you could cut down a slightly longer bolt easily enough. It is best to fit a nut before cutting and then chamfer the end slightly to make fitting easier.
https://www.amazon.co.uk/s?k=m10+1.25+cap+screw&ref=nb_sb_noss
Let me know if you don't succeed in finding them. Maybye I know someone
 

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The bolts are M8 x 1mm x 50mm long (16 or 17mm thread length) on my twin spark.

The bolts on the V6 must be different, but if you made a mistake I can sort you out with new 8mm ones.

What size socket head did you use?
The M8 bolts have a 6mm allen key head
 

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Discussion Starter #6
Yeah the V6 must have larger bolts, as they are definitely M10s. Although the thread pitch I’m not 100% on so il try those amazon ones thanks!
My only concern is that how can I be sure these amazon bolts are up to the same standard as the originals... seeing as they take quite a high shear load
 

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Indeed there is no shear load rating for bolts, as they are never supposed to be loaded in shear. They should be done up tight so they clamp the assembly together, so all load is tensile.
 

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Discussion Starter #9
Thank you.

By the way, for anyone else struggling to find these bolts:
These are the bolts for the rear inboard brake discs for Alfa 75 3.0 V6. Choose 15mm threaded option. They’re a little shorter than the originals, but do the job fine.

M10 x 1.00 x 30mm Socket Capscrew A2 (Threaded 15mm) (DIN912M10x1.00x30) @ £3.30 each

https://www.a2stainless.co.uk/M10-x-1-00-x-30mm-Socket-Capscrew-A2_A4A7M.aspx
 

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Looks like the ones you have linked to are stainless steel? Which you can't use as they are much, much weaker than a 10.9 grade cap screw.
 
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